The little Linux distribution that could: tomsrtbt

The Linux community frequently discusses the pros and cons of various
Linux distributions. We constantly seem hear the question, "But which
distribution should I use?" The answer to this question often
depends on the needs of the user. Some distributions excel as desktop
systems while others do better as servers.

But, when the issue is technical support, there are only two distributions
that I keep with me: the LinuxCare distribution and tomsrtbt (frequently
pronounced "Tom's Root Boot"). Today, we will examine the
Thomas A. Oehser's marvelous little distribution, tomsrtbt version
1.7.361.

According to its Web page, "tomsrtbt" is short
for "Tom's floppy which has a root filesystem and is also bootable." It
also claims to be "The most GNU/Linux on one floppy disk" -- and this is
one distribution which lives up to and beyond its hype.

Functions

Now, I can hear some people ask, "What can a Linux distribution
that fits on a single floppy disk do for me?" The answer is "plenty."
You won't want to run your enterprise on this particular distribution, but
it might very well bail out your enterprise from time to time. Tomsrtbt
can be an important tool in your toolkit.

Those of us who have been around long enough to remember MS-DOS boot
floppies may be skeptical at first. After all, a single DOS floppy was
lucky if it could format disks and read files from a CD-ROM. It was
sorely restricted in its utility. You were lucky to get 20 usable
commands, and real networking was almost always out of the question.

Not so with tomsrtbt. Currently using Linux kernel 2.0.36, Tom's
manages to cram some 200 modules and utilities onto a single floppy.
These range from the programs needed to mount and format disks, to support
for some PCMCIA devices. There are even pint-sized versions of vi and
EMACS, so that almost no one's editor religion will be offended.

No, there's no GUI. But what do you want in a mere 1.722 megabytes?
That's right -- Tom's manages to cram an extra 20% of data onto a standard
floppy drive. Unbeknownst to most users, most standard 1.44 floppy drives
can support floppies written in a 1.722 MB format. There's a chance that
your machine might have trouble reading the diskette, but I have only had
that happen once in the past few years.

Installation and use

How do you install it? Simply download the kit from Tom's homepage and
unpack it under Linux or Windows. Put an error-free floppy in the drive
(the error free part is critical) and invoke the installation script (full
directions are found in the FAQ at the Web site). In a few moments, you
will have a floppy containing tomsrtbt.

To use the distribution, simply insert the floppy into the drive, tell the
BIOS to boot from the floppy if it is not already set to do so, and
reboot. During the bootup, you will be asked to identify a video mode to
use (I almost always use 25 lines by 80 characters) and the keyboard to
use (for most of my machines, this is standard U.S. keyboard). Once bootup is
complete, you can eject the floppy from the drive. Tom's will have
loaded its entire Linux operating system into memory.

You can log in as "root" with password "xxxx". As a previously mentioned,
there is no GUI, because the X Window System takes up far too much space for
such a tiny distribution. But if you are using Tom's, you need to know
what you are doing anyway. In such a small distribution, there aren't too
many crutches to lean on (there is a small set of man pages, though). So
if you can't do what you want from the command line, Tom's is not a good
choice for you.

Capabilities

So what can you do with this tiny distribution? Well, you can do the
basic functions, like copying files and doing backups via tar and cpio.
But you can also do more advanced functions, like networking via TCP/IP
(for certain network cards). Dhcp and telnet clients are provided, and
the versatile wget program can download files via ftp and http. There are
even telnet and rsh host daemons to allow for incoming connections from
other machines on the network. In fact, the list of programs supported is
quite remarkable.

But, if you need functionality that is not in the base distribution, the
download sites provide an impressive list of add-ons, from support for
Samba to tape drive functions. The add-ons also include support for
numerous ethernet devices, file systems, and SCSI controllers.

The FAQ includes information on how to customize tomsrtbt with these
add-ons or other programs you may need. In fact, there is also a kit
(called ElTorito) which gives you the ability to create a bootable
CD-ROM. If you have Linux-based diagnostic tools for networking and so
forth, this capability can be especially powerful. By creating your own
Tom's CD-ROM with your own toolkit on it, you have the ability to run these
diagnostics on any machine -- even if it doesn't normally run Linux.

Practical uses

But what practical purposes does this distribution serve? I have
discovered numerous uses for it over the years. For example, every new
(or new to me) PC that comes into my possession boots tomsrtbt at least
once. I do it as a basic hardware check, to see what devices are
recognized by the operating system. Examining the dmesg log allows me to
see quickly if the devices discovered by Tom's match what I believe to be
on the machine. If the network card is a common type, like an NE2000
clone, I can even test network connectivity.

In the case of problems with a machine, Tom's can be invaluable. When a
piece of hardware seems to be malfunctioning, it is helpful to determine
if the problem lies with the hardware itself or with the software driving
the hardware. With Tom's, you can address common hardware with an
operating system that doesn't suffer from any configuration mistakes you
might have made.

This is especially useful if the PC in question has Windows loaded on
it. If a Windows PC is having a problem, booting Tom's can often allow
you to determine in short order if the problem is in the hardware or in
the Windows software. If the hardware works fine under Tom's, then your
Windows software may be the problem. If the hardware fails under Tom's as
well as Windows, then the hardware is likely the culprit.

Some time ago, I was faced with a problem: Someone asked me to load
Windows 95 on an older Thinkpad that had no CD drive attached to it. The
distribution was an OEM kit, in which one needs to boot from a floppy to
run the procedure that formats the hard drive. Then, the computer copies most of the CD distribution into a directory on the drive. After this, the computer
needs to be rebooted from the hard drive and the installation begins in
earnest. But how could I do the installation if the laptop had no CD
drive?

Tom's proved to be the solution to my dilemma. I booted the laptop from
the Windows boot floppy and formatted the hard drive. Then I rebooted
under Tom's. With the aid of an NE2000 clone PCMCIA card, I used wget to
copy the needed files across the network from another Linux machine that
had the Windows CD-ROM mounted on it. Once the copy was complete, I
rebooted from the Windows hard drive and continued the installation as
usual.

On another occasion, a friend had a Windows machine that had developed a
serious problem. Some setting in an INI file had been so messed up that
the machine would not boot up to the point where it could be fixed. Once
again, Tom's came to the rescue. Booting the PC under tomsrtbt, I could
mount the Windows drive and edit the file in question. With the offending
directive out of the way, my friend could now reboot under Windows and
reconfigure his system correctly.

The verdict

Tomsrtbt is a marvelous Linux distribution. Armed with an impressive
array of capabilities, Tom's delivers a portable utility platform
for rescuing PCs hampered by damaged software. It also serves as an
excellent diagnostic tool. No technical support engineer with Linux
knowledge should be without it.